Is hypotension a reliable indicator of blood loss from traumatic injury in children?

Background: Traditional surgical teaching stresses that hypotension is an indicator of loss of circulating blood volume. The purpose of this study is to critically evaluate hypotensive injured children for evidence of a hemorrhagic insult. Methods: Over a 2-year period, data were collected prospectively from children injured via a blunt mechanism. Systolic blood pressure (SBP) was recorded in the field and on arrival to the emergency department. Results In all, 194 injured children were identified as hypotensive. Only 82 (42%) had identifiable injuries to account for significant volume loss. Children 0 to 5 years old had a 61% incidence of isolated head injury (46 of 76) and only a 34% incidence of hemorrhagic insult (26 of 76). Children 6 to 12 years old had a 31% incidence of isolated head injury (22 of 72) and a 52% incidence of hemorrhagic insult (38 of 72). Finally, patients more than 12 years old had a 33% incidence of isolated head injury (15 of 46) and a 39% incidence of hemorrhagic insult (18 of 46). Conclusions: Hypotension should not be viewed only as a potential marker of loss of circulating volume, but also as a possible indicator of head injury in young trauma victims.